[Case of primary racemose hemangioma of the bronchial artery without presenting any symptoms].
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Publications and source records attributed to S Kubota.
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Murine NK cytotoxicity is regulated by two families of MHC class I-specific receptors, namely Ly49 and CD94/NKG2. We developed a single-cell RT-PCR method to analyze expression of all known Ly49 and NKG2A genes in individual NK cells and determined the receptor repertoires of NK cells from adult and neonatal (1-wk-old) C57BL/6 mice. In adult mouse NK cells, up to six different receptors were coexpressed in random combinations. Of 62 NK cells examined, 42 different patterns of receptor expression were observed. Most of them expressed at least one Ly49, whereas NKG2A was detected in 32% of the cells. Over 75% of them expressed Ly49C, I, or NKG2A, which are thought to recognize self-class I MHC (H-2b). Coexpression of multiple Ly49 receptors and NKG2A was stochastic. In contrast, very few neonatal NK cells expressed any Ly49, but almost 60% of them expressed NKG2A. These results demonstrate that adult NK cells are quite heterogeneous and have diverse receptor repertoires. They also suggest that the expression of NKG2A precedes Ly49 expression in NK cell ontogeny, and NKG2A is a major inhibitory receptor in neonatal NK cells.
The Ly-49 family of inhibitory receptors plays a major role in regulating mouse NK cell cytotoxicity. Two of its members, Ly-49C and I, are recognized by the mAb 5E6, which also defines a subset of NK cells involved in the hybrid resistance phenomenon. Previous studies have shown that Ly-49C binds to a broad spectrum of class I MHC molecules, while Ly-49I apparently does not bind to any class I MHC molecules tested. In the present investigation we have defined the amino acid residues of Ly-49C that are critical for determining its ligand specificities. First, using quantitative COS cell adhesion assays, we demonstrated that Ly-49CB6 bound to Dd, Db, Kb, or Kk as well as to murine leukemic cell lines GM979 (H-2s) and IC-21 (H-2b). In contrast, COS cells expressing Ly-49IB6 did not significantly bind to any of the class I MHC tested. To determine which amino acid residues of Ly-49C are critical for their specific binding to class I MHC, a series of chimeric and mutant Ly-49C and I were generated and tested. Exchanging the critical residues between Ly-49C and I significantly affected their binding specificities. Finally, we identified the epitopes on Ly-49C recognized by mAbs 5E6 and 4LO3311 that functionally inhibit Ly-49C recognition of its ligands. These results further define the class I specificities of Ly-49C and provide insight into the structural basis for how class I MHC is recognized by the Ly-49 family of NK receptors.
To analyze the regulatory mechanism of connective tissue growth factor expression, the 3'-untranslated region (3'-UTR) of CTGF cDNA was amplified from HeLa cell RNA. Direct nucleotide sequencing revealed a single major population in the amplicon, which was nearly identical to other sequences. Subsequently, the effect of the 3'-UTR on gene expression was evaluated. When it was fused downstream of a firefly luciferase gene, the 3'-UTR strongly repressed luciferase gene expression. Interestingly, the repressive effect of the antisense 3'-UTR appeared to be more prominent than that of the sense one. Together with the fact that several consensus sequences for regulatory elements are found in it, these results suggest the involvement of multiple sets of regulatory elements in the CTGF 3'-UTR.
Cerebrotendinous xanthomatosis (CTX) is a hereditary lipid storage disease characterized by hyper-cholestanolemia, cerebellar ataxia, xanthoma, and cataract. We hypothesized that cholestanol in serum of CTX patients might induce neuronal cell death in the cerebellum and eventually lead to cerebellar ataxia. To gain support for this hypothesis we developed hyper-cholestanolemia rats by feeding cholestanol. Neuronal cells, especially Purkinje cells in the cerebellum were stained by Sudan black B only in the cholestanol-fed rats, indicating the deposit of cholestanol in cerebellum. To examine effects of cholestanol in vitro, cerebellar neuronal cells were cultured with cholestanol. The cholestanol concentration increased and the viability decreased in cells cultured with cholestanol. Apoptosis was evident in cells cultured with cholestanol more frequently than in control cells, determined using the terminal deoxynucleotidyl transferase (TdT) dUTP nick end-labeling (TUNEL) method. As activities of interleukin-1beta-converting enzyme (ICE) and CPP32 protease were increased in cells cultured with cholestanol, all these data taken together suggest that cholestanol induced apoptosis of cerebellar neuronal cells. Our observations may explain the mechanism of cerebellar ataxia of CTX patients.
The nuclear and nucleolar targeting properties of human ribosomal protein S25 (RPS25) were analysed by the expression of epitope-tagged RPS25 cDNAs in Cos-1 cells. The tagged RPS25 was localized to the cell nucleus, with a strong predominance in the nucleolus. At the amino terminus of RPS25, two stretches of highly basic residues juxtapose. This configuration shares common features with the nucleolar targeting signals (NOS) of lentiviral RNA-binding transactivators, including human immunodeficiency viruses' (HIV) Rev proteins. Deletion and site-directed mutational analyses demonstrated that the first NOS-like stretch is dispensable for both nuclear and nucleolar localization of RPS25, and that the nuclear targeting signal is located within the second NOS-like stretch. It has also been suggested that a set of continuous basic residues and the total number of basic residues should be required for nucleolar targeting. Signal-mediated nuclear/nucleolar targeting was further characterized by the construction and expression of a variety of chimeric constructs, utilizing three different backbones with RPS25 cDNA fragments. Immunofluorescence analyses demonstrated a 17 residue peptide of RPS25 as a potential nuclear/nucleolar targeting signal. The identified peptide signal may belong to a putative subclass of NOS, characterized by compact structure, together with lentiviral RNA-binding transactivators.
Murine cytomegalovirus (CMV)-encoded protein m144 is homologous to class I MHC heavy-chain and is thought to regulate NK-cell-mediated immune responses in vivo. To examine the effects of m144 on NK cytotoxicity in vitro, various cell lines were transfected with wild-type m144 or a chimeric construct in which the cytoplasmic domain of m144 was replaced with green fluorescence protein. Burkitt lymphoma line Raji expressed a significant level of m144 as determined by anti-m144 mAb binding or the green fluorescence of the fusion protein. The level of m144 expression was relatively low compared with that of transfected murine class I MHC Dd. However, m144 on Raji cells partially inhibited antibody-dependent cell-mediated cytotoxicity of IL-2-activated NK cells. NK cells from the CMV-susceptible BALB/c as well as those from the resistant C57BL/6 mice were inhibited by m144. Antibodies against the known murine NK inhibitory receptors Ly-49A, C, G, and I did not affect the inhibitory effect of m144. These results suggest that the murine CMV class I MHC homologue m144 partially inhibits NK cells by interacting with a novel inhibitory receptor.
A case of a primary esophageal pseudosarcoma associated with an independent type 3 tumor is described herein. A 60-year-old male presented with dysphagia and chest discomfort. A clinical evaluation revealed a type 3 tumor in the middle of the esophagus, which was diagnosed after a biopsy to be squamous cell carcinoma (SCC). A subsequent gross examination of the subtotally removed esophagus revealed a polypoid tumor adjacent to the type 3 tumor. Histologically, the polypoid mass was composed of SCC and mesenchymal components without a transitional zone. The tumor was thus classified as a pseudosarcoma of the esophagus, and was unique in that this appeared to have developed independently from the SCC.
The cDNA encoding a 23-kDa piroplasm membrane protein (p23) of Theileria sergenti Chitose (C)-type was isolated and its nucleotide sequence was determined. The gene encodes a polypeptide of 223 aa with a 28 residue N-terminal signal sequence and a hydrophobic, valine-rich, C-terminal transmembrane domain, as deduced from its nucleotide sequence. Southern blot hybridisation analysis proved that p23 gene was a single copy gene and had allelic forms of the gene in the parasite population. By PCR, the open reading frames of T. sergenti Ikeda (I)-type and Theileria buffeli (B)-type p23 were amplified from genomic DNA and their nucleotide sequences were also determined. Comparison of C-type sequence with that of I-type and B-type revealed 90.5% and 93.5% sequence similarity, respectively, at the aa level. These results suggest that a conserved molecule in these benign Theileria spp. could be a candidate antigen for the development of an anti-piroplasm vaccine.
Novel gelatinolytic activities in both latent and active forms were detected in the normal organs of rat by gelatin zymography. Multiple active bands were detected in the extracts from the skin, jejunum, muscle, and kidney without any activation. These activities were inhibited by 1,10-phenanthroline or leupeptin, nor by E64, suggesting that these activities were derived from metallo-proteinases or serine-proteinases. Some gelatinolytic active bands were newly induced or enhanced by p-aminophenylmercuric acetate. These results suggest that matrix degrading activities due to metallo- and serine-proteinases were constitutively expressed in various rat normal organs.
Autoantibodies reacting with extracellular matrix proteins have been extensively studied in various autoimmune connective tissue diseases. Because of the possibility that such antibodies may play a role in orbital connective tissue inflammation in thyroid-associated ophthalmopathy (TAO), we studied the humoral immune response against specific extracellular matrix (ECM) proteins, namely: collagen types I, III, IV, V (CI, CIII, CIV, CV), fibronectin (FN), and laminin (LM). Anti-ECM antibodies of immunoglobulin G (IgG), IgA, and IgM classes were determined by enzyme linked immunosorbent assay (ELISA). Overall, sera from 50% of patients with TAO contained antibodies reactive against one or more ECM proteins, compared to 27% with Graves' disease (GD) without evident eye involvement, 28% with Hashimoto's thyroiditis (HT), and 9% of normal subjects. Serum anti-CI, anti-CIII, anti-CV and anti-LM levels were significantly (p<0.05) higher in patients with TAO than in normals. Anti-CI, anti-CV and anti-LM reactivity was antigen-specific in most TAO sera, while anti-CIII antibodies cross-reacted with other antigens. Anti-collagen antibodies were mainly of the IgG class. To determine the structural epitopes of these proteins, we performed immunoblotting studies on cyanogenbromide (CNBr)-derived peptides of CI and CV. While sera from 9 of 10 patients with TAO reacted with CI peptides, the response was polyclonal and uniform in all patients. However, only 2 of 10 TAO sera reacted with CV peptides. In conclusion, our study suggests that a variety of ECM proteins (CI, CV, LM) may be secondary autoantigens that are recognized by antibodies in TAO. While these antibodies appear to react with epitopes expressed on both native and denatured proteins, and may therefore have the potential to bind to ECM in vivo, their pathogenic role in TAO remains unknown.
AIMS: Thyroid associated orbitopathy (TAO) is an autoimmune disorder of extraocular muscles and orbital connective tissue. Identification of the principal target antigens would help the understanding of the pathogenesis of the disease and possibly lead to the development of specific therapies in the future. The purpose of this study was to measure serum antibodies against the flavoprotein subunit of succinate dehydrogenase in patients with TAO and correlate their presence with factors of TAO. METHODS: Sera of patients with active TAO of 6 months' duration or less were tested for antibodies against the flavoprotein subunit of succinate dehydrogenase. Clinical data were obtained by retrospective review of patients' charts. Enzyme linked immunosorbent assay was used to test sera for serum antibodies against purified succinate dehydrogenase. RESULTS: 38 patients with TAO and 32 healthy age and sex matched controls were included in the study. Anti-flavoprotein antibodies were detected in 24 out of 38 patients with TAO (63.16%) and in five out of 32 healthy controls (15.63%) (p<0.01). Neither age, sex, duration of thyroid disease, thyroid status, treatment of thyroid disease, smoking history, duration of orbitopathy, activity of orbitopathy, nor the presence of lid retraction were significantly associated with the presence of serum anti-flavoprotein antibodies (p>0.05). However, the total number of rectus muscles affected in both eyes of the patients was significantly correlated with the finding of a positive antibody test (p<0.05). CONCLUSIONS: Serum antibodies reactive with the flavoprotein subunit of succinate dehydrogenase are associated with extraocular muscle involvement in active TAO of recent onset.
BACKGROUND: The present study aimed to determine the psychophysiological changes induced in subjects by standard autogenic training (AT). Physiological measurements were taken under strict experimental conditions. METHODS: Thirty-one healthy students were divided randomly into two groups: the AT group and the control group. In the first session, the physiological variables were measured for all students before and after all were asked to relax in their own way. The AT group were then taught AT for 3 months, after which time the measurements were repeated. In the second session, the AT group practised the standard AT exercise, while the control group repeated their own form of simple relaxation. Electrocardiogram, plethysmogram (PTG) and blood pressure (BP) were measured while the students carried out a breathing rate of 15 cycles/min. The R-R intervals and BP were analysed by an autoregressive model for spectral analysis, and the data were compared by repeated-measures ANOVA. RESULTS: The AT group had a significant increase in the mean R-R interval and a significant decrease in the baseline deflection of the PTG in the second session. There were no significant changes in sympathetic activity except for the change in the PTG, although low frequency amplitude of systolic BP decreased slightly. CONCLUSIONS: AT was found to induce significant changes that were independent of respiration in healthy students, although paced breathing might have operated as a mental stress. The increase in mean R-R interval and the decrease in baseline deflection of the PTG were the most robust correlates of AT.
Selective cytotoxic effects of gamma-glutamylcysteine ethyl ester (gamma-GCE) against human immunodeficiency virus type 1 (HIV-1)-infected H-9 T lymphocytic cells were demonstrated previously. However, the mechanism of those effects remained unclear. Here, we report on enhanced cytotoxicity of the lentiviral lytic peptide I (LLP-I) of gp41, the envelope transmembrane glycoprotein of HIV-1, in the presence of gamma-GCE. Without gamma-GCE, the cytotoxic effect of LLP-I was transient, whereas with gamma-GCE, cell death induced by LLP-I remained continuous until termination. Of note, such effects by gamma-GCE were also observed with another unrelated amphipathic peptide toxin, melittin. These results suggest that the synergistic cytotoxic effect of gamma-GCE and LLP-I may play a central role in the molecular mechanism of the selective cytotoxicity of gamma-GCE in HIV-1-infected T lymphocytic cells.
Thyroid-associated ophthalmopathy is an autoimmune disorder of the extraocular muscles and orbital connective tissue, which is usually associated with Graves' hyperthyroidism. Well-studied markers of ophthalmopathy are eye muscle membrane antigens, reportedly of approximately 64-kDa molecular mass. One, originally identified only as the 64-kDa protein, has recently been shown to be the flavoprotein (Fp) subunit of mitochondrial succinate dehydrogenase, which has a correct molecular mass of 67 kDa. We have used purified beef heart Fp as antigen in an enzyme-linked immunosorbent assay for cross-reactive human autoantibodies. Sera have been screened from patients with thyroid-associated ophthalmopathy classified according to activity and presence or not of eye muscle disease, and from those with Graves' hyperthyroidism without eye involvement. Also examined were serum samples taken periodically from 20 patients with Graves' hyperthyroidism during 24 months of treatment of their hyperthyroidism with antithyroid drugs. Four of these patients had ophthalmopathy at the onset, 12 developed ophthalmopathy, and 4 did not develop any eye signs during treatment. Anti-Fp subunit antibodies were detected in 73% of patients with active ophthalmopathy and evidence of eye muscle involvement but only in 25% if there was only congestive ophthalmopathy. These values were 0% and 11% for patients with chronic ophthalmopathy, with or without eye muscle dysfunction, respectively. The antibodies were also detected in 14% of patients with Graves' hyperthyroidism without evident ophthalmopathy, 11% of patients with nonimmunologic thyroid disorders, 12% of type I diabetics, and 12% of age- and sex-matched normal subjects. Significantly, appearance of anti-Fp antibodies predicted the development of ophthalmopathy in 5 of the 6 patients with Graves' hyperthyroidism, who developed eye muscle dysfunction after treatment of the hyperthyroidism, and coincided with the onset of eye muscle signs in the other patient. Antibodies were not detected in any of 6 patients who developed congestive ophthalmopathy without evidence of eye muscle damage or in 4 patients who did not develop any eye signs. In conclusion, we have shown a close relationship between eye muscle disease and serum antibodies against the Fp subunit of succinate dehydrogenase in patients with Graves' hyperthyroidism.
To analyze the renal handling of therapeutic compounds observed as a non-linear process with a diffusion phenomenon, we employed a non-linear dispersion model described with a partial differential equation and solved it by using the finite difference method with an implicit scheme in a model dependent analysis. In this study, the renal handling of p-aminohippurate (PAH) was investigated in isolated perfused rat kidney, in which a 50 microl bolus of injection solution containing [3H]PAH and [14C]inulin was administered rapidly into the renal artery. The venous outflows were then collected for 15 min with a fraction collector. The renal extraction ratio of PAH was decreased from 65% to 18% as the PAH concentration in the injection solution was increased from 2 microM to 10 mM. The PAH outflow profile changed as the extraction process became saturated. With the non-linear dispersion model, the Michaelis-Menten parameters for the PAH extraction process were estimated by a model fitting calculation. The calculated values were 0.83 micromol/min/kidney for Vmax and 89 microM for Km. It was demonstrated that the model dependent analysis with a non-linear dispersion model is a useful approach to characterize renal drug handling, and is probably applicable for examining other non-linear processes which involve a diffusion phenomenon.
Two pairs of PCR primers were designed to perform nested PCR targetting of a 540 bp fragment of the nucleocapsid (N) protein gene (N gene) of porcine epidemic diarrhea virus (PEDV). The N gene of PEDV was amplified with 4 PEDV strains and 11 small intestines of PEDV-infected piglets collected from 2 farms in Kagoshima prefecture, Japan. Nucleotide sequences of the PCR products from a Korean and two Japanese strains (KKN96-1 and S1) of PEDV isolated in 1993 and 1996, respectively, were almost identical. These results suggest that the PCR is an available tool for detection of PEDV from pigs in the field, and that the two Japanese strains (KKN96-1 and S1) were genetically similar to the Korean strain.
It is generally accepted that thyroid-associated ophthalmopathy (TAO) is an autoimmune disease of the eye muscle (EM) and the surrounding orbital connective tissue in which circulating antibodies play an important role. Antibodies against EM membrane proteins of 63-67kDa mol. wt. seem to be the best markers of ophthalmopathy in patients with autoimmune thyroid disease. We purified a 63 kDa EM protein using SDS-polyacrylamide gel electrophoresis technology and TAO patients' sera as probes, digested the protein with cyanogen bromide and sequenced immunoreactive peptides. We also screened a human EM library with a rabbit antiserum against 63-65 kDa proteins and affinity purified antibodies from a TAO patient's serum that reacted with a 55 kDa EM membrane protein. From partial sequence information and from DNA sequencing of positive cDNA clones, the protein was identified as calsequestrin, a 63 kDa calcium binding protein localized in the sarcoplasmic reticulum of the muscle fiber. As determined by Northern blotting, calsequestrin was expressed in EM and other skeletal muscle but not thyroid or fibroblasts. Calsequestrin is different from the "64 kDa protein", which has been identified as succinate dehydrogenase flavoprotein subunit, which has a corrected mol. wt. of 67 kDa. Serum antibodies against calsequestrin were found in 40% of patients with clinically active TAO, but in only 4% of those with stable eye disease, and in 5% of normal subjects, by immunoblotting. Although it is possible that autoimmunity against calsequestrin plays a role in the progressive EM damage that characterizes ophthalmopathy it is more likely that the antibodies are secondary to a reaction against some other cell membrane protein, such as the novel thyroid and eye muscle shared protein G2s or the TSH receptor.